SMITHSONIAN CONTRIBUTIONS TO KNOWLEDGE. VOL. I.
ANCIENT MONUMENTS OF THE MISSISSIPPI VALLEY.
ANCIENT WORKS AT BOLIVAR COUNTY, MISSISSIPPI
Along the Mississippi river, and especially as we approach the Gulf, these regular structures increase both in number and magnitude. In Kentucky they are more frequent than in the States north of the Ohio river; and in Tennessee and Mississippi they are still more abundant. Some of the largest, however, occur in pretty high latitudes. The great mound at Cahokia, Illinois, is one of the most remarkable. It has often been described, and all accounts concur in respect to its great size. The following approximate plan will serve to give an idea of its general outline. It is of course much rounded, and its regularity to a great degree destroyed, by the storms and changes of centuries; its original plan is, however, represented to be still sufficiently obvious. The form of the mound is that of a parallelogram, seven hundred feet long by five hundred wide at the base. It is ninety feet in height. Upon one side is a broad apron or terrace, which is reached by a graded ascent. At the time this mound was occupied by the monks of La Trappe, the terrace was used as a garden. It is one hundred and sixty feet wide and three hundred and fifty long; the summit or highest part of the mound (A) measures two hundred feet in width by four hundred and fifty in length. Here formerly stood a broad, low mound, which was disturbed in preparing the foundations of a dwelling house. Within it were found human bones, and various implements of stone and pottery, probably belonging to a recent deposit. This mound covers not far from eight acres of ground, and the area of its level summit is about five acres. Its solid contents may be roughly estimated at twenty millions of cubic feet.